1. Field of the Invention
The present invention relates to an organic light emitting diode (OLED) display device. More particularly, the present invention relates to an OLED display device of which a display characteristic is improved by efficiently suppressing reflection of external light.
2. Description of the Related Art
An organic light emitting diode (OLED) display device is a self emissive display device that displays images by using organic light emitting diodes, and has a relatively smaller thickness and lighter weight compared to a LCD device, because the OLED display device differs from a liquid crystal display (LCD) device in that the OLED display device does not require a separate light source while the LCD device requires a separate light source. Furthermore, because the organic light emitting diode display device involves high quality characteristics such as low power consumption, high luminance, and short response time, the OLED device is spotlighted as a next generation display device for portable electronic appliances.
Usually, at least one of the hole injection electrodes or the electron injection electrodes of the OLED display device, and other various metal wires thereof, may reflect light that is incident thereupon from the exterior of the OLED device. Thus, when the OLED display device is used in a bright environment, the black color expression and the contrast of the OLED display device become poor due to the reflection of external light incident from the exterior of the OLED display device.
In order to solve the problems, a polarizing plate and a phase delay plate are disposed for suppressing reflection of the external light. A contemporary method that suppresses reflection of external light through the polarizing plate and the phase delay plate however has a problem where a large amount of light generated from an organic emission layer may also be lost when the light generated from an organic emission layer is emitted to the exterior of the OLED display device by the polarizing plate and the phase delay plate.
The above information disclosed in this Background section is only for enhancement of understanding of the background of the invention and therefore it may contain information that does not form the prior art that is already known in this country to a person of ordinary skill in the art.